Lens holders and eye guard for riflescopes and the like

ABSTRACT

A snap-fit holder for a lens or optical element includes an annular collar having a shoulder supporting the optical element and a sleeve that extends from the shoulder around and beyond the optical element. An annular retaining member includes a skirt fitted into the sleeve and pressed against the optical element opposite the shoulder. The skirt may include an outwardly projecting lip that snaps into a groove or notch formed in an inner surface of the sleeve to secure the retaining member to the collar and maintain a clamping force against the optical element. A resilient insert may be interposed between the optical element and either the collar or retaining member to provide a reaction force that tends to bias the collar and retaining member apart. Also disclosed are stacked kits of holders and an eye guard riflescopes and the like, to protect a user from recoil-related eye injury.

RELATED APPLICATION

This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 60/626,969, filed Nov. 10, 2004, which is incorporated herein by reference.

TECHNICAL FIELD

The technical field relates to optical devices, such as riflescopes, telescopes, and binoculars, for example; and, in particular, to holders for optical elements and eye guards for such optical devices.

BACKGROUND

Known lens retention devices for lens holders include (1) threaded rings screwed together around a lens to sandwich the lens therebetween, (2) a collar including a inner circumferential shoulder for supporting a first lens surface and a flange that is swaged against an opposing second lens surface, and (3) a retaining ring (typically a flat split ring made of spring steel) that seats in an inner circumferential groove of a collar, against the periphery of a surface of a lens held by the collar. These known lens holders have many disadvantages. For example, threaded rings require expensive thread tapping and chasing operations, and drive slots or holes for receiving special driving tools. Moreover, the manual twisting motion required for assembly of threaded rings is ergonomically problematic for assembly personnel. In a swaged lens holder, the swaging operation exposes the lens to potential damage, may generate and introduce grit in the optical device, and inherently results in variations in the flatness of the retaining structure that can exert uneven pressure against the lens surface. Lens holders with retention rings require special installation tooling for each size retaining ring and may subject the lens to potential damage during assembly. It may also be impossible to remove a lens from a holder of the kind that utilizes a retaining ring or swaged flange without damaging the lens.

When using a riflescope on a high recoiling rifle, a shooter may occasionally be struck in the face by the eyepiece end of the riflescope when the rifle recoils. Some prior art riflescopes include a rubber eye guard ring attached to the eyepiece end of the riflescope housing, which can protect a user's eye and face from injury. However, not all riflescopes include rubber eye guards, and in some instances a rubber eye guard may not be required or desirable.

The present inventor has identified a need for improved lens holders and eye guards.

SUMMARY

In accordance with certain embodiments disclosed herein, a holder for an optical element, such as a lens, filter, or transparent protective element, includes an annular collar having an inner shoulder for supporting the optical element. The collar also includes a sleeve that extends from the inner shoulder around and beyond the optical element. An annular retaining member includes a skirt that is sized to fit into the sleeve and press against the optical element opposite the inner shoulder. An o-ring or other resilient insert may be interposed between the optical element and the inner shoulder of the collar to provide an opposing reaction force in response to pressing of the skirt against the optical element. In some embodiments, the skirt includes an outwardly projecting lip that snaps into and engages a groove or notch formed in an inner surface of the sleeve to secure the retaining member to the collar and maintain a clamping force against the optical element. To facilitate assembly and proper alignment of the retaining member on the collar, the distal end of the skirt may include a leading outside diameter that is sized to slidably fit within a leading inside diameter of the distal end of the sleeve, and to thereby function as a pilot for the lip.

In one alternate embodiment, the collar includes a deformable sleeve that is captured in and swaged by an internal swaging slot of the retaining member to retain the retaining member against the optical element.

The sleeve may include exterior (male) threads sized to mate with female threads of another device, such as an eyepiece housing of a riflescope or other optical device, for example. At the base of the exterior threads, the holder may include a outer shoulder for seating against a device to which the holder is threadably attached. An o-ring may be fitted around the sleeve and against the outer shoulder, to facilitate a tight seal. An end of the collar opposite the sleeve may include a tubular extension including internal threads for mounting other items to the holder, such as other lens holders or a male-threaded filter or cover, for example. In a preferred embodiment, the internal threads of the tubular extension have the same pitch, diameter, and thread profile as threads to which the exterior threads of the sleeve are designed to mate, to allow multiple holders to be threadably attached in a stacked arrangement.

Eye Guard Accessory for Optical Aiming Devices

An eye guard accessory for detachably mounting to a riflescope or other optical aiming device preferably comprises a short tubular ring having opposing first and second ends. The first end may include exterior (male) threads sized to mate with interior (female) threads of an eyepiece housing of a riflescope or other optical aiming device, and the second end supports a cushioning element. The cushioning element may comprise an annular overmolded section of soft elastomer that wraps over a rim of the second end. The overmolded elastomer may also extend over an outer shoulder of the ring located medially of the first and second ends, for seating against the end of the eyepiece housing when the eye guard accessory is threaded onto the sighting device. The tubular ring may further include, at its second end, a tubular extension that extends from the eyepiece housing of the optical aiming device, when the eye guard is installed. Internal threads may be formed in the inner surface of the tubular extension for receiving other items, such as an externally-threaded filter or eyepiece cover, for example. The internal threads of the eye guard may be of the same pitch, diameter, and thread profile as the interior threads of the eyepiece housing of the optical aiming device.

In some embodiments, the cushioning element of the eye guard is combined with a lens holder structure and retaining ring, such as the one described above.

Additional aspects and advantages will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial view of a holder assembly in accordance with a preferred embodiment, shown holding a protective optical element;

FIGS. 2 and 3 are enlarged partial cross section views of the assembled holder and protective optical element of FIG. 1, showing detail of a snap-fit retaining structure of the holder in accordance with a first embodiment;

FIG. 4 is an enlarged partial cross section view of the holder and protective optical element of FIG. 1, showing detail of a snap-fit retaining structure according to a second embodiment;

FIG. 5 is an enlarged partial cross section view of the holder and protective optical element of FIG. 1, showing detail of an internally-swaged retaining structure according to a third embodiment;

FIG. 6 is an exploded pictorial view of a kit of filter accessories and storage caps;

FIG. 7 is an assembled pictorial view of the kit of FIG. 6;

FIG. 8 is an exploded pictorial view of a kit of an eyepiece-end and an objective-end protective optical element, with lens caps and a spacer;

FIG. 9 is an assembled pictorial view of the kit of FIG. 8;

FIG. 10 is a pictorial view of an eye guard accessory for an optical aiming device;

FIG. 11 is an enlarged partial cross section view of the eye guard accessory of FIG. 10; and

FIG. 11 is an alternative embodiment of the eye guard of FIGS. 10-11.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Throughout the specification, reference to “one embodiment,” “an embodiment,” or “some embodiments” means that a particular described feature, structure, or characteristic is included in at least one embodiment. Thus appearances of the phrases “in one embodiment,” “in an embodiment,” or “in some embodiments” in various places throughout this specification do not necessarily refer to the same embodiment.

Furthermore, the described devices, features, structures, and characteristics may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize that the inventions can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In some instances, well-known structures, materials, and operations are omitted or not described in detail to avoid obscuring aspects of the embodiments.

With reference to FIGS. 1-5 a holder 100 for an optical element 110, such as a lens, filter, or transparent protective element, includes an annular collar 120 having an inner shoulder 124 for supporting optical element 110, preferably via the periphery of a first face 128 of optical element 110. Inner shoulder 124 may preferably extend circumferentially within collar 120, but may, alternatively, comprise multiple discrete inwardly extending projections (not shown) for supporting optical element 110 at several points along its periphery. Collar 120 further includes a sleeve 130 that extends from inner shoulder 124 around and beyond optical element 110. An annular retaining member 140 includes a skirt 144 that is sized to fit into sleeve 130 and press against the periphery of a second face 148 of optical element 110 opposite inner shoulder 124. A resilient insert 150, such as a rubber o-ring or gasket, is preferably interposed between first face 128 and inner shoulder 124 to provide an opposing reaction force in response to pressing of skirt 144 against second face 148. When compressed, resilient insert 150 may also provide a seal around optical element 110 that is water tight and/or gas tight. An annular retaining channel 152 may be formed in inner shoulder 124 for preventing resilient insert 150 from slipping or being squeezed radially inward off inner shoulder 124. Retaining member 140 is securely coupled to sleeve 130 and, in some embodiments, may be detached with a tool without contacting or risking damage to optical element 110.

Collar 120 and retaining member 140 are preferably made of a durable material, such as metal or high-strength plastic, but may also be made of other materials. Collar and retaining member 140 may be formed of an aluminum alloy to match a rate of thermal expansion of common aluminum alloy housings used for optical devices such as riflescopes. Optical element 110 is preferably formed of an optical material, such as optical glass or plastic. Resilient insert 150 may be made from a synthetic rubber or other elastomeric material that is chemically stable. However, any of a variety of materials commonly used for o-rings and other resilient sealing members may be used for resilient insert 150.

With reference to FIGS. 2-4, skirt 144 preferably includes an outwardly projecting lip 160 that snaps into and engages a circumferential groove 166 formed in an inner surface 168 of sleeve 130 to secure retaining member 140 to collar 120 and to maintain a clamping force against optical element 110. Lip 160 and groove 166 may, alternatively, be reversed (not shown) so that the lip projects radially inwardly from sleeve 130, to fit in a groove formed around skirt 144. Retaining member 140 further includes a flange 170 that projects radially outward from skirt 144 to abut a distal rim 172 of sleeve 130 and prevent over-travel of retaining member 140 during its assembly onto collar 120. Lip 160 and flange 170 preferably cooperate with groove 166 and distal rim 172, respectively, to hold retaining member 140 substantially stationary relative to collar 120, following assembly. The clamping force generated via resilient insert 150 and retaining member 140 may prevent both longitudinal and rotational movement of optical element 110 relative to holder 100. The reaction forces generated by clamping of optical element 110 may also prevent longitudinal and rotational movement of retaining member 140 relative to collar 120.

Lip 160 may encircle skirt 144 to provide an even distribution of clamping force around the periphery of optical element 110. However, in alternative embodiments (not shown), lip 160 may comprise a plurality of bumps or pawls distributed around skirt 144, which fit in notches formed in sleeve 130, or vice versa. In still other embodiments, lip 160 and groove 166 are formed elsewhere on collar 120 and retaining member 140. For example, in one embodiment (not shown), retaining member 140 includes an outer skirt portion that extends around sleeve 130 and that includes an inner groove that engages an outwardly projecting lip encircling the outer surface of sleeve 130.

FIG. 4 depicts a holder 100′ according to a second embodiment, in which distal rim 172 of sleeve 130′ includes a circular ridge 182 that nests in a circular notch 184 in an adjacent surface of flange 170. Ridge 182 and notch 184 cooperate to pull sleeve 130′ inwardly after assembly and to prevent sleeve 130′ from being flexed outwardly, thereby ensuring a permanent joint between collar 120′ and retaining member 140′.

FIG. 5 depicts a holder 100″ according to a third embodiment, which omits the lip 160 and groove 166 of the embodiments of FIGS. 2-4. With reference to FIG. 5, collar 120 includes a deformable swage rib 190 that is captured in and swaged by an internal swaging slot 196 of the retaining member 140″ to retain the retaining member 140 firmly against optical element 110. Swage rib 190 is preferably located at distal rim 172 of sleeve 130″. The angle of swaging slot 196 is selected to cause plastic deformation of swage rib 190 when retaining member 140″ is pressed toward shoulder 124 and to thereby retain retaining member 140″ against optical element 110. Swaging slot 196 plastically bends or deforms swage rib 190 from a generally cylindrical shape (shown in phantom lines in FIG. 5) to a radially extending inwardly-angled shape, as shown in FIG. 5 (in solid lines). While swaging slot 196 is preferably angled inward, as shown in FIG. 5, to maintain a compact arrangement of components, it may also be angled outward, in alternative embodiments (not shown). An outwardly angled swaging slot 196 may allow holder 100″ to be disassembled by breaking retaining member 140″ along a notch sensitive region at the base of swaging slot 196 and allow optical element 110 to be removed from collar 120″ without contacting the deformed swage rib 190.

Internal swaging slot 196 advantageously may prevent optical element 110 from being subjected to damage during swaging. The depth of internal swaging slot 196 may also be carefully selected to tightly fit swage rib 190 and prevent inadvertent overtravel of retaining member 140″. The embodiment of FIG. 5 can produce a swaged lens retainer structure that is cosmetically superior to those produced by prior methods of externally forming a swage, in that the method disclosed herein typically prevents the generation of grit, visible cracks, and exposed rough surfaces common to such prior methods. By capturing the deformed swage rib 190 in swaging slot 196, the joint formed may be separated without damaging optical element 110 merely by pulling retaining member 140″ apart from collar 120 with sufficient force to deform swage rib 190 back toward its original shape or, in some embodiments, by breaking retaining member 140″.

With reference to FIGS. 2-5, skirt 144 may include a leading outside diameter 204 that is sized to slidably fit within a leading inside diameter 208 of the distal end of sleeve 130, to thereby function as a pilot for lip 160 or swaging slot 196. This piloting function facilitates the snap fit assembly of FIGS. 2-4 and the swaged assembly of FIG. 5, and may eliminate the need to use special assembly tools. For example, the pilot comprised of the leading diameters 204, 208 may allow holders 100, 100′, 100″ to be assembled with a simple hand press or light pneumatic press. The pilot may also prevent misalignment of retaining member 140 on sleeve 130.

For purposes of the claims, the term “lens” should be construed to include conventional lenses having one or more curved surfaces for causing light to diverge or converge, as well as flat optical elements such as filters, protective window elements, and other flat circular or non-circular disc-shaped optical elements. Moreover, although the embodiments shown in the figures include optical elements that are circular and lens holders having cylindrical-shapes, the scope of the disclosure is intended encompass non-circular optical elements and non-circular and non-cylindrical lens holders, unless the context indicates otherwise.

Sleeve 130 may include external (male) threads 220 sized to mate with female threads of another device (not shown), such as an eyepiece housing of a riflescope or other optical device, for example. At the base of external threads 220, holder 100 may include an outer shoulder 230 for seating against a device to which the holder 100 is threadably attached. In the embodiments of FIGS. 3-5, a sealing o-ring 240 or gasket made of synthetic rubber or another suitable resilient sealing material is fitted around sleeve 130 and against outer shoulder 230, to facilitate a seal that is preferably watertight when holder 100 is threadably attached to another device, such as an eyepiece or objective end of a riflescope or other optical sighting device. In the embodiment of FIG. 2, an ring member 250 covers outer shoulder 230 to provide a resilient sealing surface 256 that facilitates a watertight seal. Elastomeric ring 250 also preferably extends around a rim of a tubular extension 260 of collar 120 to function as an eye guard (further described below with reference to FIGS. 10-11). Elastomeric ring 250 may comprise a layer of elastomeric material overmolded onto collar 120 or assembled thereon after forming ring 250 and collar 120 in a separate manufacturing steps. For example, elastomeric ring 250 may be separately molded then installed on collar 120 by stretching elastomeric ring 250 around collar 120 until elastomeric ring 250 is seated as shown. Elastomeric ring 250 may be made from a synthetic rubber or other elastomeric material, such as a thermoplastic elastomer, or from another soft resilient material such as foam or certain types of plastics.

Tubular extension 260 may include internal threads 270 for mounting other items to holder 100, such as other lens holders or a male-threaded filter or cover, for example. In a preferred embodiment, internal threads 270 have the same pitch, diameter, and thread profile as the female threads to which male external threads 220 of sleeve 130 are designed to mate. The alternating external threads 220 and internal threads 270 of holder 100 allow multiple like holders to be threadably attached in a stacked arrangement, as shown in FIGS. 6-9. In other embodiments (not shown), outer (male) threads are formed around tubular extension 260, and tubular extension 260 has an outer diameter that is the same as the outer diameter of sleeve 130, thereby allowing the holder to be installed completely within a tubular housing or other device.

With reference to FIGS. 6-9, lens holders 100 may be protected when not in use by end caps 282, 284, 284 a, which may be threadably attached to lens holders 100. Caps 282, 284, 284 a may be formed of metal for durability. FIGS. 7 and 9 depict kits including multiple holders 100, 100 a with optical elements threadably attached together in a stacked arrangement. The stacked kits of FIGS. 7 and 9 provide compact, sturdy, watertight storage for optical elements mounted in holders 100, 100 a. With reference to FIG. 8, the kit includes two different sized optical elements in holders 100, 100 a, and further includes a spacer 288 with internal threads on opposing sides (only one side is visible in FIG. 8). The internal threads of spacer 288 may be of different diameters, to fit a holder 100 for an optical element sized to fit a riflescope objective lens and, on the opposite side, to fit a holder 100 a for an optical element sized to fit an eyepiece end of the riflescope (which is smaller than the objective in this example). Externally threaded end caps 284 and 284 a are provided to fit holders 100 and 100 a, respectively.

Eye Guard for Riflescopes and the Like

FIGS. 10-11 depict an eye guard 300 comprising a tubular ring 310 that is a simplified version of the collar 120 of FIGS. 1-5. Tubular ring 310 includes external (male) threads 316 formed in a first end 318 of tubular ring 310 and which are sized to mate with internal (female) threads (not shown) of an eyepiece housing of a riflescope or other optical sighting device. Tubular ring 310 also includes internal threads 326 formed in a second end 328 thereof opposite first end 318. Alternating external and internal threads 316, 326 may be sized to allow stacked mounting of holders 100 or coupling of covers, filters, and other externally-threaded devices to eye guard 300.

Second end 328 supports a cushioning element 340 (corresponding to elastomeric layer 250 of FIG. 2) which may comprise an annular overmolded section of soft elastomer or foam that wraps over a rim 344 of second end 328 and fills a step 348 of second end 328. In other embodiments, cushioning element 350 is not overmolded, and may be formed separately before being assembled on tubular ring 310. Cushioning element 340 may also extend over an outer shoulder 350 of tubular ring 310 located medially of the first and second ends 318, 328, for seating against the end of an eyepiece housing of an optical aiming device when the eye guard accessory is installed thereon. Cushioning element 340 may include an inwardly extending protrusion 352 that extends into an depression or undercut 354 in shoulder 350 to help retain cushioning element 340 on tubular ring 310 and to provide an enlarged seating zone 355 of resilient material for sealing against the eyepiece housing. Cushioning element 340 may have a coefficient of friction against the eyepiece housing that is greater than a bare metal or plastic shoulder 350, which may help to prevent eye guard 300 from inadvertently coming loose from the optical aiming device due to weapon recoil forces or otherwise. Cushioning element 340 may also provide a protective seal that prevents dirt and grit from fouling the internal threads of the eyepiece housing.

Tubular ring 310 may further include, at its second end 328, a radially outwardly stepped tubular extension 356 that projects axially (i.e. longitudinally) from the eyepiece housing of the optical aiming device when eye guard 300 is installed. Internal threads 326 of eye guard 300 may be of the same pitch, diameter, and thread profile as the interior threads of the eyepiece housing of the optical aiming device. Alternatively, internal threads 326 may be of a size that is different from the interior threads of the eyepiece housing, such that the eye guard 300 functions as a thread converter for the optical aiming device.

FIG. 12 depicts another embodiment of an eye guard 400 including a tubular ring 410 of plastic or metal with threads 416, 426 similar to the embodiment of FIG. 11, but in which the undercut 354 of the embodiment of FIG. 11 is omitted. With reference to FIG. 12, an resilient cushioning element 440 (corresponding to element 340 of FIG. 11 and layer 250 of FIG. 2), is overmolded so that a shoulder 455 of the cushioning element 440 proximal of a first end 418 of ring 410 is substantially flush with a flange 456 of ring 410. Flange 456 provides a first shut-off land that coincides with a parting line of the elastomer mold. A second shut-off land is provided by a step 458 at a second end 428 of tubular ring 410. First and second shut-off lands allow the mold for cushioning element 440 to close axially, which may improve the appearance of eye guard 400 by eliminating or reducing parting lines and molding flash around the outer diameter of cushioning element 440. Salient features of the design of ring 410 and the molding procedure for cushioning element 440 may also be applied to the lens holders of FIGS. 2-5.

It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present invention should, therefore, be determined only by the claims. 

1. A snap-fit holder for an optical element having opposing first and second faces, comprising: an annular collar including an inner shoulder for supporting the first face of the optical element via a periphery thereof, and a sleeve that extends from the inner shoulder and around the optical element, the sleeve including an inner surface having a groove or notch formed therein; an annular retaining member including a skirt sized to fit into the sleeve and press against a periphery of the second face of the optical element opposite the inner shoulder, and an outwardly-projecting lip that engages the groove or notch; and a resilient member interposed between the holder and the optical element.
 2. The holder of claim 1, wherein the sleeve is tubular.
 3. The holder of claim 1, wherein the skirt is tubular.
 4. The holder of claim 1, wherein the skirt and the sleeve are both circular.
 5. The holder of claim 1, wherein the collar or the retaining member, or both, are formed of a metal.
 6. The holder of claim 5, wherein the metal includes an aluminum alloy.
 7. The holder of claim 1, wherein the collar or the retaining member, or both, are formed of a plastic resin.
 8. The holder of claim 1, wherein the sleeve includes an outer surface on which male threads are formed.
 9. The holder of claim 8, wherein the collar further comprises an outer shoulder located at the base of the male threads.
 10. The holder of claim 1, wherein the collar further comprises a tubular extension opposite the sleeve.
 11. The holder of claim 10, further comprising an elastomeric material molded around the tubular extension.
 12. The holder of claim 8, wherein the collar further comprises: an outer shoulder located at the base of the male threads; a tubular extension opposite the sleeve; and an elastomeric material molded around the tubular extension and the outer shoulder.
 13. The holder of claim 10, wherein female threads are formed in an inner surface of the tubular extension.
 14. The holder of claim 10, wherein: the sleeve includes an outer surface on which male threads are formed to mate with threads in an optical device of a first pitch and diameter; and the female threads have a second pitch and diameter that is the same as the first pitch and diameter.
 15. The holder of claim 10, wherein: the sleeve includes an outer surface on which male threads are formed to mate with threads in an optical device of a first pitch; and the female threads have a second pitch that is the different from the first pitch.
 16. The holder of claim 1, wherein the resilient element comprises an o-ring positioned between the inner shoulder of the collar and the first face of the optical element.
 17. The holder of claim 1, wherein the resilient element provides a water-tight seal between the optical element and the collar.
 18. The holder of claim 1, wherein: the inner shoulder includes a retaining channel facing the optical element, and the resilient element is seated in the retaining channel.
 19. The holder of claim 1, wherein the retaining member further includes a flange extending radially outward from the skirt.
 20. A snap-fit holder for an optical element having opposing first and second faces, comprising: an annular collar including an inner shoulder for supporting the first face of the optical element via a periphery thereof, and a sleeve that extends from the inner shoulder and around the optical element, the sleeve including an inner surface having an inwardly-projecting lip; an annular retaining member including a skirt sized to fit into the sleeve and press against a periphery of the second face of the optical element opposite the inner shoulder, the skirt including a groove formed therein that engages with the lip of the sleeve to retain the collar and retaining member together about the optical element; and a resilient member interposed between the holder and the optical element. 